I am planning on getting myself a '72 K5 in the next little bit but I have a family.

I have seen some pictures with rear seats but most without. Was it an option or are these back seats custom mods??

 

i have a 85 and it is factory it has a release to fold up the seat then another one in the back to swing it up and against the back of the front seats.and bench seat will work from any truck actually..........good luck ben512v.............

 

you know where I can find speck sheets and option lists for the 1972 k5?

 

CLICK HERE for an index of the dealer brochure for your 72.

As far as the identification of your options and what else was offered, I am not sure if there is an SPI (service parts identification) label inside the glove box like on the 2nd gen K5's, but here is a picture of the one on my K5:

Sorry for the over exposed close up picture...

For more information, you could check out the listing in the LMC Truck catalog for your truck to see what is available as a bolt in option.

I will be modifying the floor in my K5 to use the later seats like what ben512v is talking about. They are nice quick-tach style seats that mount into recessed wells in the floor with a cross pin. When I have the body off, I will be putting additional supports under the floor to support the seat + occupants if the truck were to be wrecked.